[Wien] Query regarding the k path selection for a supercell

[Lyudmila Dobysheva]

19.11.2021 18:31, Anupriya Nyayban wrote:
> I have done the  band structure calculation for the case 2) ABxD(1-x)X3 
> having space group of 2-P-1 along Gamma to X, and Y-Gamma-Z directions 
> without the spin polarization. Firstly, I have performed all the steps 
> except "x irrep -p" and have found the following two band structures. 
> The band structure gives almost straight energy levels which suggests 
> almost no variations of the orbital energy levels along different k 
> points, and it makes me worried. Secondly, I have done all the steps 
> including "x irrep -p". But "x spaghetti -p" does not show any plot 
> (even not in case.spaghetti_ps) rather gives "here 1 Ci". The mailing 
> lists suggests this could be due to the fact that case.irrep (up/dn) is 
> not fitting into case.output1. But my case is without spin polarization 
> and there is no case.irrep (up/dn) files.
> https://drive.google.com/file/d/1lmvw5gHCu1toPvpE5jZC4lDNoCsANUaj/view?usp=sharing
> https://drive.google.com/file/d/138U3dxXZaIKrkuB4xXvWQj5MmtT0ME6_/view?usp=sharing

1. The first image cannot be seen, requires an access.
2. As I see in the second image there is a small dependence on k.
3. Your compound ABxD(1-x)X3 means that you have a large supercell with 
many atoms. As far as I remember, in this case the band structure is 
really folded and the lines are almost horizontal. There was something 
like fold2bloch to unfold the band structure for supercells.
4. You are to first make the lapw programs for the klist prepared for 
spaghetti, this is an often error, check it.
Do not know about irrep.

Maybe this will help...

Best wishes

-- 
Lyudmila Dobysheva
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